In the related art, electricity, gas, and water are supplied from providers and the amount of supply is measured and managed by meters installed in the consumers' houses.
The meters are equipped with a sealing device that prevents the meters from being opened after installation and prevents unfair practice, and tamper is prevented by the sealing (see Patent Document 1). Hereinafter, the configuration is described with reference to FIG. 12 and FIG. 13.
FIG. 12 is a configuration view showing a method of combining a sealing device with a terminal cover, in which a sealing device 2 has a sealing screw fitting portion 21 where a sealing screw 6 that fixes a terminal cover 3 to the rear surface of the meter main body is inserted and a separation groove 22 that allows the sealing device 2 to be easily separated when removing the sealing screw fitting portion 21 from the sealing screw 6. Further, a non-contact tag 7 is bonded to the side 23 with the separation groove 22 by an adhesive. Further, the sealing screw 6 is put into the sealing screw fitting portion 21, such that the sealing screw 6 is fitted in the sealing screw fitting portion 21. Accordingly, the sealing device 2 seals the meter main body.
FIG. 13 is a configuration view showing the state when the sealing device 2 with the non-contact IC tag 7 bonded to the side 23 is removed from the terminal cover 3, in which when the sealing device 2 is detached from the terminal cover 3, the sealing device 2 is pulled in the direction of an arrow (upward) in the figure. Accordingly, cracks are generated from the separation groove 22 and the side 23 splits, in the sealing device 2, by the pulling. Therefore, the non-contact IC tag 7 bonded to the side 23 is broken.
As described above, when the sealing device 2 is mounted at one time on the terminal cover 3, it is impossible to turn the sealing screw 6 without breaking the sealing device 2, that is, the non-contact IC tag 7, such that it is impossible to open the contents of the meter main body. Therefore, since the sealing device 2 is broken when the meter main body is opened, when another sealing device 2 is replaced, the identification information transmitted from the non-contact IC tag bonded to the sealing device 2 and the identification information stored in the meter main body do not agree with each other, such that an abnormality can be recognized.
Further, in the gas shutoff device in the related art, when it is determined that the gas pressure value abnormally decreases, the gas is shut off and after shutoff, the gas is restored, with the safety ensured (for example, see Patent Document 2). This configuration is described with reference to FIG. 14.
FIG. 14 is a block diagram of a gas shutoff device of the related art, which includes a pressure measuring unit 32, a seismoscope 12, a shutoff determining unit 13, a shutoff unit 39, a flow rate measuring unit 35, a flow rate storing unit 16, an accumulating unit 17, a display unit 18, and an automatic restoration determining unit 19. The shutoff determining unit 13, the flow rate storing unit 16, the accumulating unit 17, and the automatic restoration determining unit 19 are implemented by, for example, a microcomputer. The pressure measuring unit 32 detects the pressure in a gas supply pipe and supplies a detection output signal to the shutoff determining unit 13 and the automatic restoration determining unit 19. The seismoscope 12 detects vibration or shock due to an earthquake or other causes and supplies a detection output signal to the shutoff determining unit 13 and the automatic restoration determining unit 19. The flow rate measuring unit 35 measures the flow rate of the gas flowing through a gas channel and supplies the measure flow rate to the accumulating unit 17. The accumulating unit 17 calculates an instantaneous flow rate on the basis of the detection output signal from the flow rate measuring unit 35 and calculates an accumulated flow rate by accumulating the calculated instantaneous flow rate. The calculated accumulated flow rate is stored in the flow rate storing unit 16 and also displayed by the display unit 18.
When the gas pressure value measured by the pressure measuring unit 32 abnormally decreases and the gas is shut off, first, the pressure measuring unit 32 measures the pressure of the gas, and then, the automatic restoration determining unit 19 determines whether the pressure measured by the pressure measuring unit 32 becomes equal to or more than pre-set pressure, and when pressure equal to or more than the set pressure is ensured, the automatic restoration determining unit 19 automatically restores the shutoff unit 39 to the open state. Further, when the set pressure is not ensured in the measurement of the pressure after the shutoff event is generated, it is required to go to the place where the gas shutoff device is manually installed and restore the shutoff unit 39 to the open state by restoration, such as operating a restoration switch.
[Patent Document 1] JP-A-2006-250806
[Patent Document 2] Japanese Patent No. 3565552